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sciencehabit writes with a link to the ScienceNow site, noting an article saying the Higgs boson may already have been found in previous observations of the known universe. A theorist at Michigan state is arguing that scientists may have already found evidence for the elusive particle. The key appears to be that the particles that make up the Higgs field are of various 'strengths', and some of those particles may tug on others very weakly. "The lightest Higgs can be very light indeed, but it would not have been seen at [CERN's Large Electron-Positron (LEP)], because LEP experimenters were looking for an energetic collision that made a Z that then spit out a Higgs. That wouldn't happen very often if the lightest Higgs and the Z hardly interact. 'Just within the simplest supersymmetric model, there's still room for Higgs that is missed,' Yuan says. However, this lightweight Higgs is not exactly the Higgs everyone is looking for, says Marcela Carena, a theorist at Fermilab. 'The Higgs they are talking about is not the one responsible for giving mass to the W and Z,' she says. It can't be because it hardly interacts with those particles, Carena says. Indeed, in Yuan's model, the role of mass-giver falls to one of the heavier Higgses, which is still heavier than the LEP limit, she notes."

***Perhaps, but more importantly, it is not symmetric and has been known to attract left or right socks more strongly than the other. This explains the dryer effect.***

Doesn't the drier affect have to do with putting two pairs of black socks into the washer and getting three black socks and one blue one out of the drier? Perhaps you were thinking of the DB25 affect where when reassembling an elderly computer system you will -- with 50% probability -- find that when attempting to make the last connectio

From http://en.wikipedia.org/wiki/Higgs_boson_(fiction) [wikipedia.org] "In the science fantasy series Lexx, one character points out that although all-out nuclear war sometimes destroys all life on planets as advanced as Earth, it is much more common for such planets to be obliterated by physicists attempting to determine the precise mass of the Higgs boson particle, since the moment the mass is known the planet will instantly collapse into a nugget of super-dense matter "roughly the size of a pea."

Not just laziness -- when Slashdot first implemented ids, I refused to create one for the first few months because at the time, one of the big political arguments going around was over the right to anonymity online. I didn't actually choose to make my own posts anonymous -- I always signed them with my real name and email address -- but I opposed on general principles the idea of forum sites requiring (or "pressuring") users to create accounts.Eventually, it became clear that (a) Slashdot was going to conti

"Physicists suspect that empty space is permeated by a Higgs field, which is a bit like an electric field. And just as an electric field consists of particles called photons, the Higgs field consists of particles called Higgs bosons. The Higgs field drags on particles to give them mass, akin to molasses tugging on a spoon."

Electric fields consist of photons? If that's not a typo of some kind, would someone care to explain?

"In physics, the photon is the elementary particle responsible for electromagnetic phenomena. It is the carrier of electromagnetic radiation of all wavelengths, including gamma rays, X-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves."

"In physics, the photon is the elementary particle responsible for electromagnetic phenomena. It is the carrier of electromagnetic radiation of all wavelengths, including gamma rays, X-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves."

It took me a while to wrap my head around that as a kid. "Wait, photons are light. How can they be associated with radio, you hear that!" Who needs drugs to break your mind when you have science instead?

Kinda. It also transmits the electromagnetic charge. So if you have a charged particle (say an electron) it's constantly spewing out virtual photons that "tell" other charged particles that there's an electron around and they should either be attracted or repelled.

If there's enough available energy around you can get some real photons that carry away energy that we observe as electromagnetic radiation.

You could call the "fabric of space time" and aether too. General Relativity really sort of describes it as just that, with gravitational waves traveling e it. In string theory the electromagnetic force travels as a disturbance in the fabric of space time as well (just in a different way). All the field theories can be interpreted as having similarities to the idea of an aether. Contrary to popular science bashing, the idea never really went away, just became a little less in-your-face.So yeah, the Higg

Yep that is correct. The photon is the carrier of the electromagnetic force, and light is an electromagnetic wave. The force felt between charged particles is caused by the exchange of virtual photons. All fields can be thought of as made of quantized particles. In the case of the fundamental forces: Electromagnetism - photons, Gravity - graviton (theorized), Weak Force - W and Z bosons, Strong Force - 8 colored gluons.

Another interesting thing is that the range of the force is determined by the mass of its carrier particles. Gravity and Electromagnetism have infinite range, whereas the Weak Force has a very small range due to the mass of the W and Z (which is suppose to come the Higgs). Now gluons are actually supposed to be massless, but the Strong Force is range is still limited due to the fact the gluons have color and change interact with themselves (it's the only force that gets *stronger* with distance) unlike the

I've never been 100% clear on this. Is the weak force really infinite but just drops off to effectively-zero faster than electricity and gravity to?At least, that was the way I thought of it. You're saying (if I get it) that because the mediating particles are massful rather than massless, they're limited to sublight speeds. That is intriguing, but I don't quite follow the implications.

I've never seen an equation for weak or strong interactions corresponding to the Maxwell or Newton/Einstein equations fo

I've never been 100% clear on this. Is the weak force really infinite but just drops off to effectively-zero faster than electricity and gravity to?

Not really. Both electromagnetic and gravitational potentials have a simple 1/r dependence (because of massless mediating particles). If the mediating particle is massive then the potential is not as simple. Take the Yukawa potential which nicely describes pion exchange in the nucleus. It goes as exp(-mr)/r. Now, the Yukawa potential works for massive scalar fields. If the field is not scalar, like the W and Z bosons which are axial-vector bosons the potential is somewhat different, but the point is the same.

I've never seen an equation for weak or strong interactions corresponding to the Maxwell or Newton/Einstein equations for electricity and gravity. Is that because we just don't model weak force as a field because the particles don't move fast enough?

Electromagnetic and weak interactions has been unified for a long time now and are nicely described by a Lagrangian. The strong interaction is much more complicated because of the self-coupling of the mediating particles. But that's not to say there is no Lagrangian.

No typo. You have to differentiate between potential and force. Lets take the simple case of a scalar potential V(r) which is given by the integral over the vector field F(r) along some path C. Hence, V(r) is proportional to 1/r for both gravity and electromagnetism.

Lets take the simple case of a scalar potential V(r) which is given by the integral over the vector field F(r) along some path C. Hence, V(r) is proportional to 1/r for both gravity and electromagnetism.

Is it just me, or does anybody else think that the current state of particle physics is very similar to the complexities that had to be introduced to the Ptolemaic system for predicting the motion of planets? That is, it seems to work (more or less) but we seem to have missed a much simpler and deeper explanation that removes the need for digging down into ever deeper layers of apparently fractal particles.

I dunno, I kind of think of it like that, exp(-mr)/r just drops off a lot faster than 1/r, but it always does have a non-zero value, albeit effectively zero beyond a short range.

I've always found it interesting that they could fairly accurately model the strong force at the nucleon level as pion exchange long before they theorized quarks with color as the "real" cause of nuclear binding. It's like the layers of an onion.

"I've never been 100% clear on this. Is the weak force really infinite but just drops off to effectively-zero faster than electricity and gravity to?"

Not really.

Yes really. The Yukawa potential is technically infinite ranged, in that it never drops to zero at any finite distance. But it decreases much faster than a 1/r potential, so it "effectively" drops off to zero after a few e-foldings.

Electric fields consist of photons? If that's not a typo of some kind, would someone care to explain?

I think the author forgot to specify that the electric field is time-varying (to have an associated magnetic field). The combination of the two varying fields propagates as an electromagnetic wave ie light (photons). Take a look at Maxwell's Equations: http://en.wikipedia.org/wiki/Maxwell's_equations [wikipedia.org]

Even static electric and/or magnetic fields are transmitted via photons. They behave slightly differently than "regular" photons and so are called "virtual" photons, but they are no less real than the photons you are familiar with. (Explaining it further would require going into quantum theory.)

The statement is literally correct. Say you have a field in 3-space. That field itself is a 3-vector at every point in that space. When you make a fourier transform of the field, you get the field as a function of a momentum-like 3 vector. That vector is quantized, and the excitations of it are what we refer to as "photons". Add in special relativity, and you have the basics of quantum field theory.

Try the first chapter of Lahiri and Pal's "A First Book of Quantum Field Theory". If you've had undergrad calculus, it shouldn't be that bad.

It is the only Standard Model particle not yet observed, but would help explain how otherwise massless elementary particles, still manage to construct mass in matter. In particular, the difference between the massless photon and the relatively massive W and Z bosons

I always wondered what they use to measure the mass of elementary particles (not atoms). Can anyone explain? Also, maybe photons and higgs boson do have mass, but our instruments just aren't sensitive enough (kinda what the summary is saying)?

The mass of elementary particles is measured in units of energy (thank Albert Einstein for that connection), namely the electron-volt.
Essentially, physicists look for the amount of energy it takes for a certain particle to come into existence.
The photon does not have mass by definition, since it travels at the speed of light. The Higgs Boson, on the other hand, is expected to be quite massive.

Sorry IAAPP and while you can equate energy with mass doing so without thought causes problems. The true equation is a conservation of a four vector length. The mass is measured in whatever units you want and often in particle physics we set the speed of light c=1 but mass and energy have different units which must be accounted for so masses are often quoted as MeV/c^2 or mega electron-volts divided by c^2.

I always wondered what they use to measure the mass of elementary particles (not atoms). Can anyone explain?

Mass, energy, and momentum are related by a simple equation. If you know the momentum and the energy of a particle, then you can determine its mass.

The momentum of a charged particle can be measured from the curvature of the particle's trajectory in a magnetic field.

Energy can be determined through various means, which usually have to do with measuring the energy given off when the particle slows down when going through matter. For example, you could have a leaded glass block. As a fast-moving electron

Mostly it comes down to conservation of mass/energy. If we know we put 3 electrons and 20GeV of energy into the reaction chamber and got out 2 electrons, 10GeV and one unknown particle then that unknown particle must have a combined mass/energy to balance things out. (Remember that E=mc^2 so mass could have been converted to energy and vice vesa.)

So how did they measure the mass of the first particle? As one of the sibling posts said, put an electrically charged particle into a static electric field and watch how fast the field moves the particle (this can be observed at the macroscopic scale using gas bubble chambers).

Of course the above requires you to know the charge of the particle, so how do we measure the charge of an elementary particle? Simple! Fill the air with neutrally charged oil droplets and "spray" them with the particle. Some droplets will pick up 1 particle and some will pickup 2 or 3 or 4. Put them in a static electric field and measure how strong the field has to be to suspend the droplets against the force of gravity. You don't have to know which ones picked up how many particle, you just have to measure the difference in the required field strength. (See the Oil-drop experiment; note measuring the mass of oil droplets is hard be macroscopically possible.)

So in summary: we measure particle mass in terms of the masses of other particles. The first particle's mass was measured in terms of it's electric charge. The first particle's electric charge was measured in terms of how much force it imparted on an oil droplet. The oil droplet's mass was measured relative to a lump of platinum-iridium sitting in Paris. That lump was just pointed to and called 1 kilogram.

I always wondered what they use to measure the mass of elementary particles (not atoms). Can anyone explain?

You always can have some information on the mass from the kinematics of a particular interaction. The mass of charged particles is usually measured by a mass spectrometer [wikipedia.org]. But one way of measuring the mass of photons (chargless for sure) is to observe how they travel through a vacuum. The theory says that they are massless for one. But if they did have some small mass, they would travel slightly s

This is actually possible near the event horizon of a spinning blackhole. The zero energy state around a spinning blackhole is a particular orbit (I believe due to frame dragging, but I'm not positive), but a slower orbit must have lower energy which thus must be negative energy. The Penrose process uses this trick to extract energy from a blackhole.

Antiparticles don't have "antimass", they have normal mass. For charged particles, the antiparticle has the opposite charge. Uncharged hadrons (such as the neutron) have the opposite charge distribution (which I believe is usually/can only be detected by observing the magnetic field created by a spinning particle that has charge distributed through it). I'm not certain what property is different in other neutral particles; Wikipedia says that neutrinos and antineutrinos have opposite spins and that Z is its

Antimatter has positive mass and energy. If it had negative mass-energy, then when it annihilates with matter, it would not produce anything; it would cancel out the positive mass-energy of the matter, leaving nothing. Instead, what happens is that a ton of energy is liberated, because the matter and antimatter both have positive mass-energy.

Nicholas Cage found it after breaking into Los Alamos and finding a codebook hidden in Richard Feynman's desk which contained a simple substitution cypher pointing to the particle accelerator at Cern, where he discovered a vast underground cavern containing piles of gold doubloons stolen from all the Spanish Galleons that supposedly "sunk" in the 1500s. Hidden inside one of the chests of gold was a stone tablet containing ancient cuneiforms which had been painstakingly DES encrypted by hand, and when decryp

There's a book, Flashforward, about how the search for the Higgs Boson quantum decoheres the entire planet, and people catch a glimpse of the future for themselves in the most probable location, like a decade in advance. Kind of a depressing story, but pretty damn interesting one all the same.

This is real news for real nerds. This story requires reading of Leon Lederman's the God Particle [amazon.com] to get to the point where any amount of explanation in the summary would help. Maybe I'm exaggerating a bit, but I'd be really, really impressed if anyone could write a summary for that.

I have no idea what you're talking about. I only read the summary and I completely understand that there are different sizes of these Higgs Boson thingies that can be heavy or light, but the light ones are the red-headed step children of the higgs boson family in that nobody really wants one, and that they may or may not interact with things in particle accelerators and/or each other, and that most of them are named with letters near the end of the alphabet.I now feel fully qualified to provide insightful c

There are really not that many kinds of elementary particles. We're talking quarks (6 kinds), leptons (electrons, mus, and taus, and their associated neutrinos); and various force-mediating particles like photons, gluons (a few kinds), and a few of these other particles such as the theorized Higgs. Compare these fundamental units of particle physics to the elements, which are the fundamental units of chemistry. There are 92 natural elements, and a couple dozen synthetic ones. How can nature be so complex?Th